We are using a hadoop server & we dont want the server memory to overload. So, I have set the ulimit for max memory size and for some time it was working fine but memory was overloading before EOD. I came to know about soft & hard limits and set the hard limit for the maximum memory size in /etc/security/limits.conf file. But, the limits were not shown in ulimit -a command ouput. So, I restarted the server. Then, the limit was shown in the ulimit command output. But, memory is still getting overloaded as you can see the memory used is more than the limit set. Anyone kndly suggest me on this issue.
I wrote this because i was able to use openmpi to run mpirun on my 12-core workstation rather happily since day 1 I setup the system a few months ago. Yesterday when I tried to run a big job under mpirun, the job crashed rather quickly, the error message was something like mpirun process exited blah blah with signal 11 (Segmentation fault). Interestingly (or annoyingly) a job required less memory ran okay.
Since I never had this problem before, I thought it was the hardware failure. I called my IT guy to explain the problem and he is kind enough to suggest to put a line
ulimit -s 40960
in my .bashrc. And it works! But I have no clue why mpirun misbehaves out of a sudden, and that ulimit setting solves the problem completely. I would like to learn from this incident.
Newbie here! Our website CMS is a Tomcat webapp, which runs on a CentOS 5.6 release (Final). The webapp needs a permanent increase of the max. open files value. Currently, the site is "crashing" frequently due to continuous "Too many open files" exceptions that eventually will occur when traffic increases.
This is what I've done to try to increase the max. open files value code...
But still, when I log in (as any user, incl. root), ulimit -n shows 1024, not 16384. Am I missing something here? And, more importantly; Will Tomcat be able to open > 1024 files after my changes mentioned above?
I'd like to set the max stack size at boot time, preferably as early as possible. I had thought there's a kernel parameter for this, but I cannot find any reference to one.Adding "ulimit -s" to rc.sysinit was not effective; I've grepped /etc/init.d but it is not used subsequently. So what I currently have is my default runlevel set to 1, with no services except udev-post, then in rc.local:
Code:
ulimit -s 1024 telinit 3
3 being my normal runlevel with all necessary services. However, again that ulimit is being ignored, because after login it is still set to 8192. If after login I manually set the limit and change from 3 to 1 and back again (to restart all services), everything is copacetic.
Does anyone know why ulimit -s is ineffective prior to login or how I can set the max stack size at boot time? I'm just noticing that under "upstart" runlevel services are not controlled by rc.d content. Preuming:
#1 My desire to make F14 work without upstart, using ye olde sysinitv which weren't broke so I don't need it fixed, is going to be like p'sing up a rope.
#2 That systemd is replacing upstart so I might as well try to learn about that.
how can I get "rc.local" functionality under systemd?
I need to set ulimit values according to I used Code: ulimit -c unlimited ulimit -s unlimited ulimit -u unlimited But after I log again to my session values are set to default. Now can I set this values so they don't change after log out of after reboot?
I would like to use ulimit -St <some number> to stop a process form running once the process has exceeded the amount of CPU time specified in the ulimt arg.
I have been able to get ulimit -t (or -Ht) to kill my process, but I need the signal to be something other than 9 and other than SIGXCPU.
Is there a way to have ulimit issue a kill -<somthing else> when the cpu time specified has been exceeded?
A strange question, I guess. I'm running processes called from a c main program. The calling is performed (for now) as: FILE * res=popen(ulimit -t 1; prg args); So I can read the stdout of the process as a file and analyze it. The time limit is important for me.
2 questions: 1. How do I get to know if the process terminated on its own or by the ulimit? 2. How do I limit to times that are less than 1 sec (I have many of those).
I know that setrlimit exists, just before I change my whole approach I wanted to see if I can deal with these things from the outside.
Fedora 12 gcc 4.4.1 I am doing some programming, and my program gave me a stack dump. However, there is no core file for me to examine.
So I did: Code: ulimit -c unlimited and got this error message:
Code: bash: ulimit: core file size: cannot modify limit: Operation not permitted I also tried setting ulimit to 50000 and still got the same error. The results of ulimit -a:
Code: $ ulimit -a core file size (blocks, -c) 0 data seg size (kbytes, -d) unlimited scheduling priority (-e) 0 file size (blocks, -f) unlimited
I'm no expert on DHCP. My problem is that i have a CentOS 5.5 server on which i want to install a DHCP server. I have two NICs where eth0 has access to the internet and where eth1 should act as an DHCP server.
I have installed dhcpd and this is how my dhcpd.conf file looks like.
Code:
ifconfig looks like this
Code:
When i start dhcpd on eth1 i get no error messages but when i connect any devices to eth1 they don't get any IP. I cant find anything in any logs about devices trying to get an IP address. I dont have any firewall rules in iptables.
i compiled and install postfix, and i using relayhost that point to my ISP. but my "DNS server" is on the same server where is installed postfix. and there is running apache with vhosts so i have domain that hosted on same server and in zonefiles of my domain my MX records points to Google Apps, to google's MX servers. But when i try send E-mail via sendmail to mail@mydomainonsameserver.com it not deliver mail to Google Apps totally, if i try to send to another E-mail everything fine it deliver it. so finally i done research this problem in Internet. And find that need to disable deliver mail to localhost(localdelivery)as i think postfix understand that the domain point to the same server where postfix have itself. and try to deliver mail local. but zonefile MX record even the domain on same server can point to another server outside. So i disabled localdelivery in postfix. and problem not fixed
LDAP is endlessly not working, due to difficulties to simply configure it. I even cannot make the first steps of the installations ... It seems so difficult ... After many howto, wiki, reading, re-reading the errors are still there, always different, and not working.Is there an admin, coming from hell, that made running a LDAP server for sharing the basic configuratin files /var.. /etc... of a working LDAP Server in a tar.gz?
Whilst I have used GUI-based Linux distros for the last few years, I am now struggling somewhat when it comes to setting up a server from the command line. All the howto's I've read so far tell you how to set up certain things, but I don't know what I actually need to set up.Rather than asking the same questions all over again on a forum like this, and generally being a bit of a noob, I wonder if there's a resource somewhere that someone could direct me to in order to know what I need to do to set up a fileserver.
The hardware is all done, and I will probably set up a router distro like IpCop to manage the network, but I'm rather lost as to what packages I need, and how to know what the server is/isn't doing.I've used plenty of command lines in the past (ms dos, amiga dos, BASIC programming etc), just not a linux command line. All I've ever done is mount a few drives, use nmap and started x
I installed vsftpd server in one of my servers using "yum install vsftpd" command. NFS server is running in the other server and mounted as "/data" in this FTP server. root in FTP server has also root authority in NFS server. All the files and sub-folders under "/data" in FTP server have 755 or 766 mode. Even I modified vsftpd setting to allow root login.
When I login as root to FTP server with FileZilla client, I can see all the file list in root home directory and move to /data directory. I can download any file in a local HDD but I can not download any file in /data directory.
I am still quite new to all this but I guess we were all beginners once, this forum seems very helpful.Here is my situation, I will give as much detail as I can.I have a dedicated server which is running CentOS release 5.5.Initially I had Plesk installed, but when I upgraded PHP I damaged the Plesk configuration, and so I installed Webmin instead.
All seems to be fine with this, apart from the DNS configuration / BIND server.I know this because I have one site which uses an external DNS server and this works fine (i.e I can access it from a browser). All the others don't resolve - i.e the ones I set up in Plesk.I've done a bit of investigating to see what is going on, but I'm stabbing in the dark a little.
hey guys i am facing problem with command yppasswd on my server and clineti have configured my server well.when i run command yppasswd -p joe it shows that yppasswd is not running on master server below is error i get
[root@station226 ~]# cat service_restart service nfs restart service ypserv restart
Running web service and dhcp only on 1pc of a 4pc lan. Optomized minimal slackware 13.1 install (no GUI)on 30g fireball for only one user (myself):
Question is howto work properly in terminal environment: the rule of thumb is not to work on system as root to maintain root's integrity; since i do not have /home for users - what identity do i create to work on files safely? Can you adduser identity without /home as to not work as root? I found 'netgroup' but i am not sure that setting up the id of other machines on lan is what need to do?
I have installed bind 9.3.6 on a centos 5.4 virtual machine. i have successfully installed it and i just want to run it as a caching server but it is not working.I mean when i dig any url it gives connection time out messages .
I checked /var/log/messages on my machine and there were two kinds of messages:
Now there are a lot of errors of the above two kinds only. The only difference in the errors are the ip address that is different.
I have a sun server connected to my dell laptop for internet. I've port forwarded 21 on my router, and it's pointed to my laptops static IP (192.168.1.8). I started the ftp service on the sun, and it works fine locally. But when I try to connect to my ftp server with the external IP, it doesn't work.
I have a cron job to run every 15 minutes. The cron job is running per /var/log/cron. It lists the job every 15 minutes.
[Code]...
I do not see any errors. I also looked in /var/log/messages for any errors and it does not list any. I added a line to the script that is running to send an email to me to see if it is running or not. When I run the script from the command line, the script runs without error and I get an email. I have searched and can not find what it going on. Is there some where else errors might be? Could there be a permission issue? The cron job is not being added by the root user.
How can I verify if TLS is working for SMTP? I can see when I connect to Dovecot via IMAP4, a TLS session is present but I don't know to configure TLS for SMTP (sending messages).
I have NFS almost up and running. On the server /etc/exports is good, hosts.allow and hosts.deny are good, I can make the connection and in /var/log/messages on the server but on the client at 192.168.20.95, when I enter:mount -t nfs -o nfsvers=3 192.168.20.1:/home/nfs /home/nfs_local.It doesn't error out, doesn't come back to a prompt, it just sits there. I have verified not a permission issue.
I'm trying to tunnel and SSH connection through another server.for the tunnel is ran:ssh -L 8112:yy.yy.yy.yy:22 -N user@xx.xx.xx.xxBut when I try to ssh to localhost -p8112 I get an immediate error saying "exited: remote closed the connection
I've been trying to enable SSL in a Apache+Debian server. I already enable the ssl module, I added the 443 port in the ports.conf and I added a virtual host for the 443 port, as follows.
ErrorLog /var/log/apache2/error.log CustomLog /var/log/apache2/access.log combined SSLEngine On SSLCertificateFile /etc/apache2/ssl/apache.pem </VirtualHost>
The certificate is installed also. After I restart Apache, the error log don't show anything unusual. The only showed is this: Apache/2.2.3 (Debian) PHP/5.2.0-8+etch13 mod_ssl/2.2.3 OpenSSL/0.9.8c configured -- resuming normal operations. Still, I can't open any pages with https protocol, only with http.
